Should testing drive development or development drive testing?

“Almost no-one disagrees with the idea of testing, writes David Norfolk. but many people fail to follow an uncompromising test-centric process. Recently, I had the chance to ask Richard Collins, Development Strategist at a specialist software vendor, why he believes that test-driven development is the way to build better software. Interestingly, most of Richard’s ideas probably feature in Comp Sci courses, or did when I did one, which isn’t to say Comp Sci grads remember those parts. However, it is good to have it confirmed that “good practice” isn’t just dull theory used to pass exams, but actually helps to keep a real software company in business.”